Macrozoobenthic communities of the saline Bolshaya Samoroda River (Lower Volga region, Russia): species composition, density, biomass and production
We investigated species composition, density, biomass and estimated production of macrozoobenthos communities in the middle and mouth reaches of the saline Bolshaya Samoroda River (Volgograd region, Russia) from May 2013 to April 2014. A total of 30 euryhaline and halophilic taxa were found during the study period. There were significant differences in the species composition between both study sites that could be explained by differences in ecological conditions. The production of macrozoobenthos in the middle reach was 22.54 g dry wt m−2 yr−1, and in the mouth reach the production was 117 g dry wt m−2 yr−1. In all seasons of the year at both sites, the greatest contribution to benthic production was made by the same taxonomic groups. Diptera dominated at both sites. Amphipods were abundant only in the middle reach. In the middle reach, the greatest contributions to production were made by Gammarus lacustris, Sphaeromias pictus and Glyptotendipes salinus, and in the mouth reach, Microchironomus deribae, Tanytarsus kharaensis and Chironomus salinarius contributed to benthic production the most.